Ecandy Portable NFC Waterproof Super Bass Resonance Bluetooth Wireless Speaker With Power Bank Bluetooth CSR 4.0 Technology Compatible Outdoor Sport/ Climbing Stereo With Metal Snap Hook (Black) Waterproof, Shockproof, Dustproof Rated IPX4 for 100% protection against Water and Dust. Rubberized rugged exterior for ultimate impact resistance. Advanced Bluetooth 4.0 Technology- Ultra-optimized version of Bluetooth that consumes less energy and delivers crystal clear sound. Built-in Bluetooth Technology - Stream Music Wirelessly - Works with Virtually any Bluetooth-Enabled Device (Smartphones, Tablets, PCs, MP3 Players, etc.) Lithium ion rechargeable battery Enjoy up to 10 hours of uninterrupted playtime with a single charge. Easy hands-free music streaming and speaker phone; Power functions - Volume up / Volume down / Fast forward (skip) / Backward / Pause / Play / Power On/Off